Clinical comparison of the osteochondral autograft transfer system and subchondral drilling in osteochondral defects of the first metatarsal head

Abstract

BACKGROUND: Osteochondral defects of the first metatarsal head can deteriorate to osteoarthritis of the first metatarsophalangeal joint if left untreated. Treatment options for osteochondral defects of the first metatarsal head vary widely.

PURPOSE: To compare the clinical outcomes of the osteochondral autograft transfer system with those of subchondral drilling for the treatment of osteochondral defects of the first metatarsal head.

STUDY DESIGN: Cohort study; Level of evidence, 3.

METHODS: The authors retrospectively evaluated 24 cases of osteochondral defects of the first metatarsal head treated operatively; 14 patients underwent subchondral drilling (group A), while 10 were treated with the osteochondral autograft transfer system (group B). The association of variables of osteochondral defects with clinical outcomes was assessed in each group. Clinical outcomes were evaluated according to a visual analog scale (VAS) for pain, the American Orthopaedic Foot and Ankle Society (AOFAS) hallux metatarsophalangeal-interphalangeal scale, and the Roles and Maudsley score. The Tegner activity scale and an activity rating scale were used to determine the activity levels.

RESULTS: The mean VAS score in both groups was significantly improved (from 6.9 ± 0.9 to 3.9 ± 1.3 in group A and from 7.4 ± 0.8 to 3.4 ± 1.2 in group B; P < .05). No difference was noted between the 2 groups at final follow-up (P = .651). The mean AOFAS score in both groups was significantly improved (from 62.9 ± 5.8 to 73.2 ± 8.2 in group A and from 65.0 ± 4.1 to 81.5 ± 5.8 in group B; P < .05). There was a significant difference in mean AOFAS score between the 2 groups at final follow-up (P = .032). Large defect size (≥50 mm(2)) and the existence of a subchondral cyst were significant predictors of unsatisfactory clinical outcomes in group A (P = .047 and P = .019, respectively). Multivariate analyses showed a defect size larger than 50 mm(2) was associated with significantly worse outcomes on the last follow-up VAS and AOFAS scores in group A (P = .005 for VAS and P = .006 for AOFAS). There was no association of defect size and subchondral cyst with clinical outcomes in group B (P > .05). No association was found between location of the defect area and clinical outcome in either group.

CONCLUSION: For osteochondral defects larger than 50 mm(2) or when a subchondral cyst exists, the osteochondral autograft transfer system could potentially be used as a treatment of choice for osteochondral defects of the first metatarsal head to restore functionality of the metatarsophalangeal joint.